The SmartEncryption feature in Huawei OceanStor Pacific ensures data security. The *HCIP-Storage V5.5 Training Material (Module 3: Scale-Out Storage Technologies)* explains:

- Option A: True. “For DPC or NFS reads, self-encrypting disks (SEDs) retrieve authentication keys from the key management server, decrypt ciphertext, and return plaintext to the protocol layer.”

- Option B: True. “SmartEncryption supports encrypted writes and decrypted reads via NFS, CIFS, HDFS, and S3 protocols.”

- Option C: False. “SmartEncryption encrypts data at the storage layer. Clients using NFS, CIFS, or DPC write data that is automatically encrypted by the system before storage, not written as plaintext.”

- Option D: True. “OceanStor Pacific uses SEDs for disk-level encryption, ensuring all service data is encrypted.”

Thus, option C is false.